198688023439 has 4 divisors (see below), whose sum is σ = 200204726040. Its totient is φ = 197171320840.

The previous prime is 198688023433. The next prime is 198688023593. The reversal of 198688023439 is 934320886891.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 198688023439 - 2⁹ = 198688022927 is a prime.

It is a super-2 number, since 2×198688023439² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198688023433) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 758351104 + ... + 758351365.

It is an arithmetic number, because the mean of its divisors is an integer number (50051181510).

Almost surely, 2^198688023439 is an apocalyptic number.

198688023439 is a deficient number, since it is larger than the sum of its proper divisors (1516702601).

198688023439 is a wasteful number, since it uses less digits than its factorization.

198688023439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1516702600.

The product of its (nonzero) digits is 17915904, while the sum is 61.

The spelling of 198688023439 in words is "one hundred ninety-eight billion, six hundred eighty-eight million, twenty-three thousand, four hundred thirty-nine".